True or false: The half-life of a radioactive element is a physical constant that cannot be changed by heating, freezing, or vaporizing.

The half-life of a radioactive element is indeed a physical constant that does not change regardless of external conditions such as heating, freezing, or vaporization. This is because the half-life is determined by the properties of the atomic nucleus and the specific decay processes that occur within it. These decay processes are inherently tied to the structure of the nucleus, which is unaffected by physical changes in state.

When discussing radioactive decay, it is essential to recognize that half-life describes the time required for half of the radioactive atoms in a sample to decay, a process that is governed by fundamental physical forces at play within the nucleus itself. Hence, under normal conditions, no external physical changes, including those mentioned, will alter this measure of time.

Understanding this property helps in fields like nuclear medicine, radiometric dating, and radiation safety, as it allows for predictable calculations regarding the behavior of radioactive substances over time.